The present invention relates to a system for monitoring connectors provided in an electric system of a motor vehicle, and more particularly to a monitor for connectors employed in an air-bag system of the motor vehicle.
The air-bag system is provided in a motor vehicle for protecting the driver and passenger in case of a front end crash of the vehicle. The air-bag system has an air bag folded and packed in a housing mounted on a steering wheel and an inflator provided on the steering wheel for inflating the air bag. The inflator has a squib as a heating element, and an air bag operating circuit including a source, g-responsive sensors, and a rotatable connector for electrically connecting these components to each other. Upon a crash current from the source is supplied to the squib to heat pulverized chemicals in the inflator to explode it, so that the air bag is inflated.
Manual connectors are provided for connecting leads in the air-bag operating circuit between the squib and sensors. These connectors must be coupled with utmost care on an assembly line of a motor vehicle factory.
If one of the manual connectors is disconnected, the air bag does not operate in an emergency. Therefore, the connections of the connectors are checked on the assembly line.
FIG. 6 shows a conventional connector comprising male and female connecting members C.sub.1 and C.sub.2. A plurality of projections are provided on both the members C.sub.1 and C.sub.2, which form a predetermined bar code m when coupling. If the connecting members are completely joined, the predetermined bar code m can be read by a reader. If the predetermined bar code m can not be read, it is determined that the connector is incompletely joined.
In the conventional systems, the joining state of the connector can be inspected only on the assembly line or by a dealer at an auto shop. The connector which was disconnected and re-connected by a user cannot be checked by the user, because he can not read the bar code. Further, if the jointed connector comes loose, the driver can not find out about such an abnormality. Therefore, the conventional connector has a fatal serious defect.